QuakeIndex

Earthquake · automatic estimate, may change

M 3.1ml

Earthquake near Nikiski, AK

USGS: 28 km WNW of Nikiski, Alaska

10:40 am AKDT, Oct 9, 2026 · · 85 km deep · released about 1,300 lb of TNT

10 km30 km60 km120 km N Kenai Peninsula Borough 61 km
Distance rings around the epicentre, with the nearest towns at their true direction. Not a shaking map — see the USGS ShakeMap for that.
When
10:40 am AKDT on 9 October 2026 ()
Where
29 km (18 mi) WNW of Nikiski, AK · earthquakes near Nikiski
Magnitude
M 3.1 (ml)
Depth
85 km below the surface
Felt
no reports yet
Nearest
Kenai Peninsula Borough, 61 km SSW
Nearest mapped fault
Middle Ground Shoal anticline (Cook Inlet folds), 13 km from its surface trace — near is not the same as on
Status
Automatic — a machine’s first estimate, which may change

USGS · last changed by USGS · we first saw it 2 hours ago

A magnitude 3.1 earthquake was recorded 29 km (18 mi) WNW of Nikiski, AK, at 10:40 am AKDT on 9 October 2026 (18:40 UTC). This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

At this magnitude and depth it was probably too small to be felt, even directly above it. In Nikiski, 29 km away, the estimate is intensity II (weak). Estimated from magnitude, depth and distance with the intensity equation USGS Did You Feel It? uses; felt reports, where there are any, are the measurement.

How big was it?

This earthquake released about 1,300 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 4.1 would have released about 32 times as much.

  1. Northridge, California 1994 M 6.7 250,000× the energy of this one
  2. Mineral, Virginia 2011 M 5.8 11,000× the energy of this one
  3. Magna, Utah 2020 M 5.7 7,900× the energy of this one
  4. This earthquake M 3.1 about 1,300 lb of TNT
  5. Around the size people start to feel M 3.0 this one released 1.4× more

Energy from the Gutenberg–Richter relation (log10E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.

For this area

The largest earthquake within 50 km since 2016 was M 5.2 on 2017-05-30 — about 1,400 times the energy of this one.

Before 2016, the USGS record lists 12 earthquakes of M5 or more within 50 km; the five largest:

  1. 6.8 Southern Alaska · 45 km NE of this epicentre
  2. 6.7 6 km WNW of Nikiski, Alaska · 22 km SE of this epicentre
  3. 6.4 19 km SSE of Tyonek, Alaska · 38 km ENE of this epicentre
  4. 6.0 Southern Alaska · 44 km N of this epicentre
  5. 5.8 17 km NW of Beluga, Alaska · 49 km NNE of this epicentre

Since 2016: the QuakeIndex catalogue (US, M1.5+), built from the USGS FDSN event service. Before 2016: USGS ComCat, M5+ from 1900. Distances are between epicentres. This is the record, not a forecast.

Where

Epicentre 60.8290, -151.7370. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection from the epicentre
Kenai Peninsula Borough, AK 61 km (38 mi) SSW earthquakes near Kenai Peninsula Borough

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

No further earthquakes have been recorded within 50 km since this one.

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

Revisions

USGS refines a solution as more stations report. Every change we have seen is listed here.

What changedFromToWhen
longitude-151.74-151.74
depth84.484.5
magnitude3.23.1

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.